This Article Full Text (PDF) Submit a scholarly reply Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by McGuire, G. Articles by Wennberg, R. Search for Related Content PubMed Articles by McGuire, G. Articles by Wennberg, R.

COMPARISON OF REMIFENTANIL- AND ALFENTANIL-INDUCED EEG ACTIVATION IN EPILEPTIC NEUROSURGICAL PATIENTS

Department of Anaesthesia, Toronto Western Hospital, University Health Network, 399 Bathurst Street, Toronto, Ontario, Canada M5T 2S8

INTRODUCTION

Short acting narcotics are known to stimulate EEG activity in patients with temporal lobe epilepsy. However, the potency of narcotic-induced EEG activation is agent dependent1. The purpose of this study is to compare for the first time the EEG activation effects of the newer short acting narcotic remifentanil with those of alfentanil during neurosurgical procedures for epilepsy.

METHODS

With appropriate institutional approval, informed consent was obtained from patients scheduled for craniotomy with resection of epileptogenic focus. The design was a randomized double blind cross over study. Anesthesia was induced with propofol (1-2mg/kg), fentanyl (3-5mg/kg) and muscle relaxant. Maintenance of anesthesia consisted of N₂O/O₂, isoflurane and muscle relaxant.

EEG electrode contact strips were positioned over the brain at the level of the temporal lobe cortex, amygdala and hippocampus. Twenty minutes prior to EEG monitoring, the isoflurane was discontinued and droperidol IV 0.02mg/kg was administered. At the time of the study, the N₂O was discontinued. The EEG was recorded for 10 minutes before and after the study drug (either alfentanil 30mg/kg or remifentanil 1mg/kg). When the EEG had returned to baseline the sequence was then repeated with the second study drug. Postoperatively, the EEG activation (spikes and sharp waves) was analyzed by a neurologist using standardized criteria. EEG data were analyzed using the Friedman test and the Wilcoxon signed rank test.

RESULTS

Thirteen patients were entered into the study. The mean age was 30.6+13.5yrs, the female/male ratio was 7/6 and the mean weight was 67.5±13.4 kg.

Although both drugs increased EEG activity, the most potent activator was alfentanil. The systolic blood pressure was lowered by approximately 15% at 3 and 5 minutes after both drugs, returning to baseline after 10 minutes.

The present report compared EEG activation by alfentanil and remifentanil. Alfentanil was more potent in inducing electrocorticographic spiking activity compared to remifentanil. Such narcotic induced stimulation of seizure foci does assist the surgeon in selecting or confirming resection location during epilepsy surgery.

REFERENCES

Anesth Analg 1999; 88: 1101–6.[Abstract/Free Full Text]

This Article Full Text (PDF) Submit a scholarly reply Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by McGuire, G. Articles by Wennberg, R. Search for Related Content PubMed Articles by McGuire, G. Articles by Wennberg, R.